Ace wagged his tail at the praise from his mommy. "Wuff!" he barked, muffled by the leash. Looking at the door to the station, he first tried to use the same strategy on this one as he had the last, only to discover it was pull, not push.
Backing up, Ace dropped his leash from his mouth and reared up on his hind legs again. Using the other door as a point of leverage, he got as firm a grip as he could on the door handle and pushed off, pulling the door open about a foot or so before losing his grip. Plopping down, Ace put himself between the door and its frame, opening it wider and stepping aside for Barbara to get through without tripping over him. The technique wasn't perfect, and his partially-toothless mouth had left a nice slobbery surprise for the next person that grabbed the handle, but it got the job done.